BY THE BOOK: Lethem works in a collective artists’ space by the Gowanus. Photo: Christian JohnsTon(2)

Job Much-lauded author of novels including “Motherless Brooklyn,” as well as short stories, nonfiction and comics.

Lethem, a winner of the 2005 MacArthur “genius” award, toils in a communal artists’ workspace by the Gowanus Canal, a few blocks from where he was raised and six blocks from where he currently lives. Just before his son, Everett — now 2 — was born, he fled from his home office to this fourth-floor walk-up overlooking the sludge-filled waterway.

Raised in pre-gentrified Boerum Hill, Lethem is often asked for his take on the changing neighborhood. “It still has an industrial wasteland feel,” he says, adjusting his brown glasses, which match his brown corduroys and convey a youthful nerd-chic vibe belying his age (45). “It’s a nourishing view.”

Desk Pointing to an antiseptic-looking stainless steel desk salvaged from a medical supply facility in Toronto, Lethem proclaims it “talismanic,” as it’s where he wrote his critically acclaimed “Fortress of Solitude.”

A treadmill is jammed up against it. He explains the jerry-rigged system: a wireless keyboard and a giant computer-font setting allow him to walk and work simultaneously.

“After a hike, when I could barely breathe, I realized how sedentary I’d become. Painters stretch canvas, but writers only exercise their fingers.”

DÉcor With clutter and unpacked boxes belonging to other inhabitants accumulating in the corners, the space has an unkempt, work-in-progress feel. The dark wood floor is splattered with white paint. A church tower, visible out of the primary window, worked itself into his new novel, “Chronic City,” as a contemplative, mysterious symbol.

“I grew up an artist’s kid, so studios are home,” he says. “It’s not maximum comfort, but I feel dedicated to the space.”

Detritus A pointy silver modernist sculpture — a gift from his German publisher — sits on a shelf, a stack of CDs teetering nearby. A framed issue of “Omega the Unknown,” a comic he revived in a 10-part series, hangs on one wall. Dog toys, a bowl and a blanket welcome Maisie, his Jack Russell terrier, who visits a few times a week.

Work style Focused energy. “These days it’s very precise. I used to let other things intrude, but that was a luxury. Now [with a child and another on the way] I have one shot each day.”

Routine While his wife, a filmmaker, snoozes, Lethem plays with his son for a couple of hours until 9 a.m., when the nanny comes.

“I’ve always been a morning writer. Between breakfast and lunch I do my writing for the day. Unless I’m in the finishing throes, then I find galactic reserves of energy.”

To drown out the clanking of the heater in winter (“it sounds like building’s about to explode”) he puts headphones on and listens to music — indie rock, soul, funk, jazz.

“For each book there’s an emotional playlist. In “Chronic City” one of characters is obsessed with Rolling Stones’ “Shattered,” but it’s not a music book in the way “Fortress” was.”

Philosophy “I’m not the fastest writer, but working every day is the holy grail.”

What’s next Lethem’s begun a novel set in Greenwich Village and Queens. “I’m excited about the idea, but it’s just a start.”